The goal of this research is to study the role of facial affect recognition deficits and social threat sensitivity in a sample of adolescent (ages 14-17) first-degree relatives of people with schizophrenia (HR-SZ) in order to better understand social dysfunction and sub-threshold symptoms of psychosis. 40-75% of HR-SZ adolescents qualify for a major mental health diagnosis and 4-22% will eventually develop a psychotic disorder. Social dysfunction is a key marker for predicting which HR-SZ people will develop schizophrenia; however, little is known about specific pathways to dysfunction during late adolescence. Facial affect recognition deficits, difficulty decoding facial emotions in others, are present in HR-SZ people and predict psychosis and social dysfunction. Sensitivity to social threat may also be an important marker of psychosis risk and predictor of social dysfunction, as preliminary evidence suggests that HR-SZ adolescents report greater sensitivity to threat in daily life and have a hypersensitive pattern of cardiac autonomic responding characterized by slower return to baseline heart rate variability pattern after exposure to threats. The proposed study will examine whether excessive sensitivity to social threat (assessed through cardiac psychophysiology) and facial affect recognition deficits predispose HR-SZ adolescents to a pattern of increasing symptoms and social dysfunction compared to controls over three time points: baseline, 6 months later, and 1 year later. Sensitivity to social threat and facial affect recognition deficits are characteristic of those with schizophrenia and their relatives but not specific to them; these domains have been identified as NIMH Research Domain Criteria (RDocs), and thus the proposed research should have relevance to the study of psychopathology across diagnostic boundaries. The proposed study would also provide the first-known use of ecological momentary assessment (EMA) to examine social dysfunction and sub-threshold symptoms of psychosis in daily life for HR-SZ adolescents. Starting the second year of the proposed funding period, EMA methods will be combined with ambulatory heart rate variability to examine how daily life measures of autonomic functioning relate to baseline laboratory-assessed sensitivity to social threat and behavioral EMA responses. To appropriately evaluate her research questions, the candidate will receive training in social and neurobiological aspects of typical and prodromal adolescent development, longitudinal study design and data analysis, and assessing psychophysiological response to threat with laboratory and ambulatory cardiovascular responding. Her mentorship team has extensive experience in developmental psychopathology (Dr. Silk), developmental processes contributing to risk for schizophrenia (Drs. Haas and Walker), advanced longitudinal data analysis (Dr. Molenaar), and heart rate variability assessment (Dr. Jennings). By investigating cognitive and affective underpinnings of social dysfunction and symptoms in HR-SZ adolescents, the proposed award should provide useful targets for future research seeking to improve early identification and interventions to prevent psychotic disorders and other psychopathology.